#10363 HIGH 11.3.1: Auto-Suspend gets in the way when sharing over Salut

Zarro Boogs per Child bugtracker at laptop.org
Wed Feb 8 04:34:56 EST 2012

#10363: Auto-Suspend gets in the way when sharing over Salut
           Reporter:  erikos           |       Owner:  erikos                           
               Type:  defect           |      Status:  reopened                         
           Priority:  high             |   Milestone:  11.3.1                           
          Component:  telepathy-salut  |     Version:  Development build as of this date
         Resolution:                   |    Keywords:                                   
        Next_action:  no action        |    Verified:  0                                
Deployment_affected:                   |   Blockedby:                                   
           Blocking:                   |  

Comment(by erikos):

 I have spend a bit more time diagnosing the current stuation. We have two
 prominent paths where suspend could badly interact with the collaboration

 * presence: state changes are not propagated correctly (e.g. A does share
 an activity but the state change does not reach machine B because it is in

 * during sharing: changes are not propagated correctly (e.g. A is in a
 shared Memorize game with B and A flips a card while B is seeping and B
 gets no notification about that move)

 I have been testing with two 1.5 XOs running the latest 11.3.0 build
 (883). They both were collaborating on a link local connection (salut).
 This test was done WITHOUT the inhibit patch from above. The presence
 changes were always (despite once out of 20) propagated correctly. To
 verify I opened the neighborhhod view on A, while A felt asleep I shared
 an activity on B. A was waken up and the state was transferred correctly.
 I have repeated this several times.

 As a second test I shared a Memorize game on A and joined on B. While in a
 shared session the machines did never suspend, even if I left them idle
 for minutes and gave the adversaries enough time for thinking which tile
 to flip. There is every few minutes a tiny moment (maybe millisecond)
 where the 'suspend'-light turns off and then on again and I presume one
 would need to hit that exactly to maybe loose a change, but I doubt this
 is possible let alone likely. Same test results were achieved doing the
 same test in Write.

 I conclude that the inhibit-inactivity-while-sharing Sugar patch will not
 bring an improvement to the current situation. Currently the machines do
 not suspend while in a shared session (due to the chatty happening in the
 background). I am happy to hear about any other results. If there are
 other sync-up problems in Activities I postulate that they are activity
 specific. There are other bugs (see
 http://wiki.laptop.org/go/Release_notes/11.3.0#Sugar_collaboration) that
 affect the presence in the neighborhood view, believing my testing results
 I don't think suspend/resume is the major player there (fixing packet loss
 still welcome of course).

Ticket URL: <http://dev.laptop.org/ticket/10363#comment:21>
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